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             Light enters one end of the fiber from a light bulb, laser, or some other source, and travels essentially unimpeded all the way to the length of the fiber where it is intercepted by a photosensitive detector such as an electronic device or the human eye. The distance of travel varies according to the use to anywhere from just a few inches to over one hundred and fifty miles. Fiber optic cable can transmit large amounts of information over one hundred and fifty miles almost instantaneously. "While it takes five hours to transmit the contents of an encyclopedia over copper wires, the entire work can be transmitted in les than a minute over fiber optics" (Yawn).
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